Traveling wave amplifiers



June 9, 1959 DENcH 2,890,372

TRAvELNG WAvE: AMPLFERS F11ed Feb. 23, 1956 IJnfted StateS Ptent This invention Tolotes fo o tfovoling vvave an1plifief, and, n1ofe oaTtioulafly, to a tunable backWad Wave trve1ing vvave aIIlplifiof opab1o of ooeration ovef a Te1 ie1y vide fTeqllency fange.

Traveling wave aniplifiefs afe koown Which include a pefiodic s1ow Wave enorgy pfopagating structuTe, an elongated electrode spaced fToff1 and SubStantially coextensive vith said stTuctuTo and IIlaintained 'at a nega tive potential With ToSpct thefeto and in caSeS in vhich fhe afoTeSaid electTode is not eleotTon-eII1iSSive, an electTon un for pTodooing on olectron beam which fTavelS thfough the iIftefoction oace betvvooo Said StrnctuTe and the nogafive electfode. A dio ffequeocy input Signal is coupled adjacent one eod of tho periodic structore, and ovving to tho iotofootion betvveen the electfon bean1 moving a1ong a path adjaoeot fhe peTiodic Structufe and the electfoInagnefic field of the adio fTequency vvave propagating along Said StrootuTe, the input signaL undeT the pTo )er conditions, is amped; thiS ampHed Sig nal nTay be eXtfacted ffon1 said pefiodic stTuctnTe ad jacent the othef end thefoof.

The electroInagnotic field along S11ch a Stfl1ct11fo Inay be consideted to conSist of an in1i11ito nun1beT of Supef iInposed fraveling vvaves of Space hofII1onicS each having a phaSe ve1ocity v given by Whero o iS equa1 to the ofodct Z7r and tho fTequency, iS the itch of length of one 11etvvork section vvhich iS sobStantially identica1 fo1 each section, 1 is the phase shift peT section and iS fhe noInber of the space haT n1onic, for exam le 1, 2, etc. The hase har- Inonics l1ay bo eithef poSftive oT negative, depending 11 on the valIle of vvhon X has a positive vallle, the phase velocity iS in fhe san1e difection aS the eneTgy of gfono velocity and fho coffeSponding phaSe fla1'- monicS olay be refeffed to a fofwaTd waveS. on the oter hand When v iS nogative, fhe ohaSe velocity iS iI1 a diTection opposifo to tflo enefgy of group e1ocify and the oof eSpoodio WaveS then a1 e fefeffed to `aS nega fivo spaoe hafn1onios of baokvvafd vvaveS.

If, for eXaInp1e an eleoffoo beam oWS in fhe difectio11 of ono of theso bckvvafd vvaves at a velocity SI1b Staotiany equa1 to the phase o1ocity, fof a given f1 e qoehcy, of the bckWafd Wove, intefaction W111 take placo betWeen th beam and offoveling wave snch that eIlefgy vVi11 be ffanSfeITed ffonf fhe electfon beaTn to the electfoo1agoofio e1d aod the enefgy given to the backWard wave,wi11 oo tiiI1sf(11(d along the pefiodic StI1ctufe in a' difeofioo ooposffe to that of the electron Inoveoent If the eloctfon beaIn coffent iS below a ofitical cUfent where oScillations caf1 begin, and When the eleotTon beao1 velooity iS SobStantially eqoal to the ve locity of one of t11e negativo of backWaTd space haf n1onics an ampHed signa1 n1ay be extTacted at the eod of the pefiodic structure away fron1 vvhich the electron beam is being difected.

In a backWafd Wave aInplifier, the electfo11 bea-n n1ovo throogh Inutllally pefpendicular electric and n1 gnetio fieldS, both of which are Sobstantially nofn1a1 to the elec the electron beam- The velocity each of the backvaTd waveS of Space harInonicS of a traveling fadio ffeqoenoy vvave vafioS vvith freqoency in periodic stfuctofes of the typo de Scribed. T1e avefage velocity of the eloctfon bean1 in tubeS of tho type deScfibed is dependent upon the eleotfic field strength E and the nlognetic e1d st ength B, and iS equal to the Tatio E/B, Whefe E iS fuTthef dotof n1ined by the fatio of the voltage v betvveen the pefiodic st111ctuTe and the negative electrode to the (1istoI1ce d therebetvveen. AS the velocity of the eleotron bean iS vaed, substantia1 SynchToniSII1 nlay be obtained With the phaSe velocity of one of these harn1onics and an1- plification n1ay be accon1pliShed vvithin tho tfaveling Wave tube. owing to the fact that tubes of fhe pfiof aft afe chafacteTized by unfform beam velocity, SynchTonisoo Inay be obtained vVith the phaSe velocity of a given haf n1onic ovef only a conlpaTatively naffovv ffeqoency band.

In accordance vith tlliS invention, the negative elec fTode of the tTaveling vvave aInplief iS inclined at ao aI1gle relative to the peTiodic delay struct11re soch that the Spacing f, instead of being constant throoghoufthe length of the tube, graduany changes along the length thereof. AS fhe distaI1ce d changeS, tho elecffio field StfeIl th 1, fof a given valne of B, likevviSe vafies. The average electfon bean1 velocity, vvhich iS pTopofoonal to the value of E, thuS vafieS along the length of the tube, and anlplification oveT a relatively Wide band of ffe quencieS Inay be achieved. The width of this band iS deteTII1ined by the slope of the negatfve electfode.

^AlSo iI1 accoTdance vith this inveotion, the avefoge electTon bean1 velocity Inay be vaTied by tapeTing the tfanSverse olagnetic fleld. The tranSvefSe II1agnetic field Inay be fapered fegafdleSS of vvhether of 11ot the pTevioI1Sly deScribed n1eans for vafying the electTio field iS en1ployed.

()thef objectS and featufeS of thiS invention Wi11be coIne 1nore appafent aS the desoTiption progfeSSeS, ref efence being Inade to the accoInpanying dravingS vvf1erein= Fig. 1 iS a cfoSSsecfional view, taken along line 11 of Fig. Z of o traveHng Wave ampHer accofding to the invention;

Fi g. Z iS a Sectional view of tho an1p1ieT tube i1lus trated in Fig. 1

Ffg. 3 iS a detail vieW i1111StTating a portion of tho anodo asseInbly of the aII1I)1i1ieT tube of Fig. 1;

Fig. 4 is a detail v1eW illllStrating the electron gon aSSeInbly of the amplifief of Figs. 1 aod Z;

Fig S is a schen1atic diagTam of an aIT1plifief tubo siIni laf to that of Figs. 1 and Z vvherein a lineaT configI1Ta tion, fathe than an afcoate configuration, iS used;

Fig. 6 is a Schen1atic diagTan1 of a n1odification oftho Hnear an1plifier tube Shown i11 Fig. and

Fig. 7 is a view inuStTating n1eanS foT gradually vafy ing tlle In agnetic field, Tather than the elecffical 1ie1d, of an aInplifier tube sllch aS that ShovI1 iI1 FigS. 1 and 2.

1eferriI1g now to FigS. 1 to 4, a traveling vvave tube aInplier 20 is Shovvn vhich con1priseS an anode asSeInbly Z1 vVhich inclLdeS a periodic sloVv wave energy pTopagat ing StrL1ct11re or anode delay line ZZ, an elongated eleo trode 30, soInetiI11es Tefeffed to as a so1e, maintained negative with Tespect to anode delay line Zz, a loadinaSSeInbly 4ro, an output coupling TneanS 50, an e1ecfon gun Inoonting aSseInbly o0 fLIIther including at 1east cathode of and heater oZ, an inpot coupHng meaos 70,

leayed fingefS of elon1ontS, Such as 24 and 24, as Shovvn in Figs. 1 to 4, o oh of Which afe connected together fof difect ouffent. The anode delay line 22 of Fig. S, aS Well aS that of the device of Figs. 1 to 4, may be any Suifable pefiodic slow vvavo pfopagafing StTI1ctufe othef than an intefdigital line, Such aS a helix, a vane-type Stfuctllfe, of the like. In the device of Fig. 5, the e1ongated elecffode of sole 3@ iS affanged coeXtenSive vvith the anode delay lino 22, and, like the lattef, is of linea1 conotfuction. ]f1o sole iS inclined vvith Tespect to the anode delay lfne so that a tapefod intefaction Space be tWeen anode delay line 22 and sole S is obtained. The Spacing befween the anodo delay li11e and the sole gfadu any docfeaSeS ffofn a value f to a value aS fhe inpI1t ond of the anode delay line, that iS, The end of the delay line eleotfically fenlote froIn the electfon gun, is ap pfoached, Tho intenSity E of the electTic field betv/een the sole and the anode delay line iS deteTInined by vl1efe X is the voltage betveen the anode delay line and the cathode, fflat is, the voltage acfoSS souTco X is the voltage betvveen the cathode and the Sole, that iS, the voltage acfosS Source 107; and cf is flle spacing betvveen the anode delay line and the Sole at any giVen poinL In son1o instances the cadode and Sole I1ay be at the SaIno difect ouffenf potential; in thiS event, the elecfTic field E befween the Sole and the anode delay line is de tefInined siInply by the fatio I /f,

The Inagnefio eld B tfanSvefse to tho elecffic fe1d E is maintained unifofm along he lengt11 of the tube, either by USfng a single Inagnef of by enlploying an affay of Inagnets of identical fiox density- InaSnluch as the aveTage electTon beam velocity is directly pToportional to the 1afio of the intenSity E of t11e afofeSaid electfio field and the intenSify B of the tTansvefse nlagnetic fiefd, if n1ay be seen that the frequency band vzidth of operation vvin eXtend ffoIT1 a ffequence detefnlined by the fafio jE /B to a ffequenoy detefn1ined by the fatio f /f vvhere E and E aTe (ed, TeSpective1y, by the values Z and (f The dth of the fTequency band isdetefInined by fhe aInonnt of Slope of the sole, vhile the n1ean ffequency of this band iS deteflnined by the voltage between the anodo delay line and the sole.

II1 Fig. 6 a linear backvafd Wave aInpliiiof 20 iS Shovn vvhefein the Sole 30 is inclined vifh Tespect to fl1e anode delay line 22 So hat the S )acing thefebetvveen continU onSly increaseS froIn a value f at the ontput end of the fube to a larger valIle (f at the input end, aS contrasted with the tube of Fig. Whefein the Slope of the sole is of opposite s enso. The ffequency band vidfh of opeTa tion win be fhe same in the ttlbe of Fig. 6 aS in tho tube of Fig. 5. The bfoadband an1I)1ifiefS thos faf doSClibed depend upon the gradoal vaTiation of electfic eld in tof1Sify E vith di Stance along the fube; hovevef, aS pfevi ouSly n1entioned,- he beaIn velocify of the electfon iS dofofInined by the 1afo-f/f ConSequently, the spacing botyveen tho sole and the anode delay 111ay be Inaintained 111ifofIn while the Inagnetic field strength is gradually vd- 1ong the length of tfle tube. SLlch an affange nloot fof a cylindTioal tfaveling Wave aInplffief iS iI1dicated in Fig. 7. A tfasvefSe IT1agnetic field thefoof iS pfovided by n1eans of an aI fay of cloSely Spaced U-Shaped nlIfefS 32 cifo11Infefentially arranged about the anode aSSembly 21 and WhoSe feSpecfive pole pieces So ond 8 re in SubStantial aligoInnt with the unifoTn1 inteTaction Spaoe, not viSible in Fg- 7. The l11agnetS afe indicoted aS electfonlagnets, each having a vvinding 8 connected across a Single nnidifectional soUTce of votoge 38 Colnmon to n of flle WidingS. The intensity of the mag netic field aSSociated vvith each Tnagnet dependS upon the nombef of tufns of the fespective winding. AS Shown in Fig. 7, the magnet neafest the output end of the anode deloy 1ine,that iS the Tnagnet iost to the left of output coupling nUInbef 60, iS pfovided With the feWest numbef of tUTns. Tho nun1bef of ooil fofns on soocesivo II1ag fletS is gfadually iocfeaSed along tho length of the tllbe, and the Inagnet adiacent tho inpllt end of the anode delay line, tllat iS, fhe n1agnet iI1St to the fight of the ioput coupling 7@ in Fig. 7, caffieS tho gfoateSt nun1bef of tufnS. In this way, the fiux dei1Sity of each succeeding nlagnet iS incfeased and a gfaduany incfeasing n1agnetic field iS obtained as fhe input end of amp1er 2f is appToached. The nlagnetS n1ay, of coufSe, be efnlanenf rnagnetS fat11of than electfoInagnetS, pfovided only that the Stfength of these olagnets iS gfadoony incfeaSed. The continuity of the vafiation of tlle niagnotic neld iS de tefn1ined by the nunibef of n1agnetS usod, the Spacing of the ITlagnets, and the felative SffeI1gth thofeof. The I11idffeqoency of the oporating band of ho 1plifief Inay be Vafied by adjuStn1ent of tffo nlagnitodo of the eXciting voltage ffoIn souroe 88. The ffequonoy band vvidth of the aInplifieT of Fig. 7 like thot of Fig. S, is considefably gfeater than that obtainable vvith pfiof backvard vave afIlPlifiefS in vvhich both the electfic and nagnetic e1dS afe unifofn1.

The n1agnetic field Inay be gTaduaHy altefed in the opposite difecfion to that indicated in Fig. 7, fhat is to say, the lnagnetic field strength Inay be increaSed aS the output end of the aInpHeT is ppfoached,

It is fufthef poSSible to graduany vaTy both the electfic beaIn Strength and the Inagnetic field Strengtl1 con curfent1y ThiS invention is not linlited to the pafticulaf detailS of consfruction, niatefialS and pfocosSes descfibed, as IIlany equivalento vvill SI1ggeSt theniSelveS to thoSe skilled in tlle aff. Fof exan1ple, although the ta1efed negative eleCtrode has been shown aS an a11Xiliafy elecffode of Sole sepafate ffom the cathodo, the Ifegative eleotfode f1ay take the fofIT1 of a continuous electron-eIniSSive cathode oxtending tITe length of the tube. Fufthefnlofe, it is not eSSenfial that the electronlaghetic of nlagnetic field be varied continuously, So long as vafiationS of E and B coffesponding to each of fho deSifed freollencieS in the pasS band afe attained along the length of the ao1pH er ttlbe It iS dosifed, accofdingly, t11af the ap ended claio1S be given a bfoad intefprefation coITIn1ensufate with the Scope of the invenfion Within the art.

What is claiIned iS= i, A v ide band trave1ingWavo elocffon diScharge de vice conpriSing a periodic Slofv wave energy pTopagafing net Mvofk for tfansInifting electfonlaghetic vvave enefgy, the pitch of said network being conStant throughout a Inaio1 portion thefeof, n1eanS fo'r directing a beaIn of e]ectronS along a path adiacenf Said netwofk in one1`gy inforactfng folationShip With Said wave energy, Safd IneanS fof difeC ing including Ineans for producing InUolaHy perpendiculaf lfnidirectional eleofric ond Inagnetic fieIdS in the region of Sad oath and SubotanfiaHy norfnal therefo in )ut co1 pHng fneans positioned adjocent tho ond of Said netvork toVafd Which electrons are oirected for inSeffing an in pnt signal containing at leaSf ono diScrefe ffe Llency coInponent into Said deviCe, ontpufIneanS dispoSed adiacent the end of Said nctWork aw8y froh Whch Sao e!eCfros are directed, and Ineans fof vafying the infenSity of af foaSt oe of Said e1dS along Said path.

2- A wide band ffaveling avo eleCffon dSchafgo de vice conlpTiSing a periodic slow vave enefgy propagafng netvvofk fof f[anEI11itfing eeCtToff1agnot vaV eneTgy, the pitCh of said net /ofk beng constant throughout a I1ajor poftion thefeof, IneanS fof directing a beaIn of electfonS along a path adjacenf Said netWoTk in enefgy infofacfing relationShip vvith Said ave energy, Said 11eanS fof d... recfing inolIlding nleanS for ofoducing n1HtuoHy perpen dCnl UnidifeCtona e!ectric and InagnetiC oIdS in tho region of Said paths and subStantiany noTn13l thefeto inpI1t coupling n1eanS positioned adiacent the end of said network tovVafd which electfonS a e difected fof inSefting an input Signa1 containing at leaSt one diScfete ffequency coolponent into said device, output IIlea11s disposed ad iacent the ond of said netWork away fron1 Which said electTonS aTe difected, and IneanS fo1 gTaduany vaTying the intensity of at least one of Said fields along Said path.

3. A Wide band tfaveling vvave electfon diScharge de vice coInprising a periodic Slovv vVave energy propagating netvvoTk for tfanSIT1itting e1ectfo1gnetio vvave energy the pitch of Said netvvoTk being conStant throughont a Inaior poftion theTeof, II1eanS foI' directing a beam of electronS along a path adiacent Said I1etWork in energy interacfing Telationship vvith Said vvave energy, Said n1eanS for difecting including n1eans fo1 pfoducing InutuaHy perpendiculaf unidirectional electfic and Inagnetic e1dS in the Tegion of Said path and Substantiany nofnlal thereto, in ot coupling nleanS positioned adjacent tho end of said TletvVork toward Which electfonS are directed fof inSerting an input Signal Containing at leaSt one discrete ffequency con1 ponent into Said device, output Ineans diScloSed adiacent the end of Said netvvork avvay fronl Which Said electTons are diTected, and IneanS for vaTying the intensity of Said electfic field along said ath fo1 peTInitting aIn lincation of Said inpnt Sfgnal.

4. A vide band tfaveling Wave electfon discharge de vice coInpTiSing a periodic Slov vave energy pfo agating netvork fol franSInitfing eloctToInagnetio wavo energy, the pitch of Said Iletvvork Jbeing conStant throughout a Inajor poTtion thereof, nleans for directing a beaTn of electronS a1ong a path adiacent Said notvvofk in eneTgy interaCfing relationShip vvith Said Wave energy, Said n1eanS for diTect ing inclIding Ineans fo1 pTodnciog Inutuany perpendicUlar unidiTectional electfic and nlagnetic fields in the region of Said path and Substantially noTnal thefeto, input Cou pling n1eans positioned adiacent the end of said netvvork tovaTd vvhich electfo1S are direcfed fo1 inSerting aI1inpUt Signal oontaining at least one diScrete frequency con1 ponent into Said device, output Ineans diScloSed adiacent the end of Said netvvork away frolT1 Which Said electTonS afe difected, and Ineans for varying the inteI1Sity of Said Inagnetic field along Said path for perIT1itti11g aInpHncation of Said input SignaL 5. A de band tTaveling vvave electron diSchafge de vice con1priSing a peIiodic slovv vvave energy propaJgating netvofk fof tfanSfT1itting electfoInagnetic Wave energy, the itch of Said netvvoTk being conStant thronghout a Inaiof portion thefeof, n1eans foI directing a beaIn of electTonS along a path adjacenf Said netvvork i11 energy intefacting TelationShip vvith a backvvafd coInponent of Said Wave eneTgy, Said IneanS for difecting including n1eanS fof pro ducing ITlutually peIpendicular Unidirectional electric and Inognetic neldS in the region of Said path and SubSfantially norn1al therefo, input coupling TneanS positioned odiacenf the end of Said netWoTk towafd vvhich electronS are directed for^inSerting an input Signal oontaining at leaSt one discrete frequency conlponent into Said device, output 1oanS diScloSed adiacent the end of Said network avvay froIn vhioh Said electronS are difected, and n1eanS foT vaTying the i11tensity of said fields along Said path fof pefn1itting aInp1ication of Said inpllt SignaL 6. vvide band tTaveling vave electron diScharge de vice coInpriSing a periodic slovv vvave energy propagafing netvvoTk foI transo1itting electroTnagnetic vvave energy, the pitch of Said netWork being constant throu ghout a Inaior poItion thefeof, I1eaI1S for directing a bean1 of electTonS along a path adiacent Said netvvork in energy intefacting Telationship vvith a backvvard coInponent of Said vvave enefgy, Said o1eanS foI directing incloding IneanS for pro ducing InI1tllally pefpendicnlar unidirectional electTic and Inagnetic fields in the fegion of Said path and SubStantially nofInal thereto, input coupling nleans 1)ositioned adjacent the end of said netvvork foWafd Which elecfrons afe di Tected fof insefting an inp11t Signal containing at leaSt one diScTete frequency coInponent into said device, output Ineans diScloSed adiacent the end of Said netWoTk avvay ffon1 vvhich Said electfoI1S afe difected, and n1eans fof incTeaSing tho intenSity of Said electfic field along SEid path aS Said output TneanS is appoached.

7. A vide band traveling vave electron diSchaTge de vice conlpfiSing a pefiodic Slovv vvave energy pTopagating net`voTk fo1 transnitting electTon1agnefic waZe energy, tho pitch of Said netvvork boing conStant thfoughoUt a Inaio1 oftion theTeof, IneanS fo1 difecting a bean1 of electrons along a path adiacent Said network in energy intefacting relationShip vith a backvard coInponent of Said vvavo enoTgy, Said n1eans fof difecting inclIlding IneanS fof producing InlItoally peTpendicular Unidirectional electric and n1agnetic fields in the region of said path and SubStantiany norInal thereto, inp11t Collpling nleanS poSitioned adjacont the end of Said netvVOTk tovvard vvhich electronS are di 1ected for inSerting an inpI1t signal containing at leaSt ono diScrefe frequency con1ponent into Said device, output ITlea11S diSclosed adacent the end of said netvvoTk away fron1 vvhich said electfonS are directed and Ineans for varying the intensity of Said Inagnetic field along Said path for perolitting aInplification of Said input signaL 8. A vvide band traveling Wave electfon diScharge de vice coInprising a periodic Slow vave energy pfopagating netvvofk for tTanSfnitting electronlagnetic vave enefgy, the pitch of Said netvVork being conStant throI1ghout a Iaio poftion thereof, n1eanS for diTecting a bean1 of elect1onS along a path adiacent Said netvvoTk in energy intefacfing relationship With Said vvave energy, Said Ineans fo1 diTect ing including IneanS for producing ITlIItllally perpendicular nnidirectional electTic and T1gnetic eldS in the Tegion of Said path and SubStantially noffnal thereto said II1eanS fo1 directing further including an electTode spaced ffoIn and SUbStantially coeXtenSive vvith Said pefiodic netWofk, input coupling Inea11S positioned adjacent the end of said netvvoTk tovvard vvhich electrons afe diTected fof insefting an input sig11al containing at leaSt one discrefe frequency CoITlponent into said device, output nleanS diScloSod ad iacent the end of said network avvay ffon1 vvhich Said electTonS aTe directed, and Said electfode being inc1ined at an angle vvith TeSpect to Said netvvofk.

9. A vvide band tfaveHng Wave electron diSchafge de vice coT11)fiSing a pefiodic S1ow vvave energy pTopagating network for tTanSInifting electrolTlagnetic vvave energy, tho )itch of Said netvvofk being constant throughont a Iajo1 poftioI1 theTeof, n1eanS for directing a beaIn of electronS along a path adjacent Said netvvork in energy inteTacting TelationShip vvith a backward conlponent of said vvave energy, Said IneanS for directing inc1Ilding IIleans fo1 pro ducing Tnutually pefpendicUlar 11nidirectional electric and IT1agnetic fields i]1 the Tegion of said path and subStantiany norInal thereto, said IneanS fo1 difecting fllftheI including an elecfrode Spaced fron1 and SubSfantiaJIy coextensive vvith Said periodic netvvork, and Inainfained at a negafive potential vvith Tespect to Said netvork, input coupling IneanS positioned adiacent the end of said netWoTk tovvard vvhich electTonS aTe diTected fof inSefting an input Signa1 containing at least one diScreto ffequency coInponent into Said device, oIItput nleanS diSclosed adiacent the end of Said netvvofk aWay fron1 vvhich Said electTons aTe diTected, and said electrode being inclined at an angle vith Tespect to Said netvvoTk Such that the Spacing betvveen Said olectrode and Said netvvork decTeaseS aS Said output 1eanS iS appfoached,

10. A vvide band traveling vvave electTon diSchaTge device con1pIiSing a efiodic slow vvave energy propagating netvoTk fo1 tranSn1itting electroInagnefic vave energy, the pitch of Said netwoTk being constant thTougho11t a Inaiof poftion theTeof, IneanS for directing a beam of electfonS aloITg a path adiacent Said netvork in enefgy interacting TelationShip vvith said vvave energy, Said n1eans for diTecting including Ineans fo1 pro ducing n1Utuany peTpendicular unidiIectional electfic and nlagnetic fieldS in the region of said path and SubStantially nofn1al theTeto, input coupHng TneanS ositioned adiacent the end of Said network toward Which electTonS are di fected fof insefting an in )11t Signal containing at lealSt ono disofefe ffequeocy coInponent into Said (1 ico onf put Ineans disclosed adiacent tho end of Said netvvoTk avvay fron1 vvhfch said electronS afe direoted, and an ar fay of IIlagnefs of diiferent field Stfength afranged along Said path 11. A vvide band fravoling vvave electfon diScharge device con1pIising a periodic S1ov Wave enofgy 1)1opagating netvoTk for tranSInitting electron1agnetic vVave enefgy, the pitch of aid netvvofk bei1Tg conStant throughout a Inaiof I)()rtion thefeof, IneanS for diTecting a beaTn of electronS along a path odjacent Said netvvofk in energy intefacting rolationship vith said vave energy, Said nleans for directing including IneanS for pfoducing Inutllany perpendiCUlar unidiTectionaI electfic and Inagnetic fieldS in the region of soid path and sUbStontially noTnal theTeto input coI1 pling IneanS positioned adjacent the end of Said netVvork tovaFd vvhich electfons afe diTected for insefting an in put signa1 containing at least one diScrete frequency oonponent iiito Saio device, olltpI1t IneanS diScloSed adiacent the end of Said netvvork awa from vhch Said electronS afe difocted, and an array of nagnetS of different field Streogtlf arraoged along said path in the ofdeT of their roSpective field stTengths.

12. A Wido band tfaveling vvave eleotfon disoharge deviCo con1pIiSing a periodic slovv v/ave energy pfopagating netWork foT tranSmittiog eloctrofnagnetic Wave eneTgy, the pitch of Said oetWoTk being constant thTooghout a, Inaior -poion theTeof, IneanS for directing a` beam of electrons along a path adiacent Said netvvork in energy intefacting Telationship With a baol(vard conponent of Said wave eneTgy, Said nleanS fof difecting i]1clllding n1eans for pro dLlcing Inlltually peTpendicular 11IlidiTectional electric and ITlefgnetic fields in the regioI1 of said path and Substantially nornlal thereto, inpI1t coupling Ineans positioned adiacent the end of Said netvvofk toward ovhich electronS are di- Tected fof insefting an in ut Signa1containing at least ono diSofete ffequency cofnponent into Safd device, output n1eanS diScloSed adiacent the end of said netvvofk away froII1 Which said electronS are direcfed, and an affay of mgnetS of diffeTent field st1,ength affanged along said path in the ofder of their respective field stTengthS,

13. A Wide band traveling vvave electTon diScharge devfce ooInpfising a periodic Slow vvave energy propagating netvvork for tfanSTIlitting electroInagnetio Vvave eneTgy the pitch of said netvvork being conStant throughout a, Inaior portion thereof, meanS for directing a beam of electfonS along a path odiacent Said netvvork in energy infefacting TelationShip With said wave energy, Said IneanS for directing including n1eans for prodocing lnutually peTpendicHlaf unidiTectional electfic and Inognetic iields in the fegion of Said path and subStantiaHy norInal thereto an electrode spaced fron1 and substantially Coextensive With Said pe riodic netwofk, and Inaintained at a nogative potentia1 vVith reSpect to said netvvork, input coupling meanS poSi tioned adiacent the end of said netvvork towaTd vhich olectronS are directed fof inseTting an inptlt signal con taining at least one diScrete ffequenoy con1ponent into Said devico ootput neanS diSclosed adiacent the end of said netvvofk avvay froIT1 vhich Said electrons aTe directed, Said electrode f)eing inclined at an angle `vvith respect t() Said ]1etvvofk, and Said IneanS fof producing a Ingnotic field including a plurality of IIlagnetS of diefent eld strength positioned along Said pad1.

14. A Wide band traveling wave electI'on dischafge de vice con1pTising a pefiodio slow wave energy pTo1)agating netvvofk fof tranSInitting electfon1agnetic Wavo en ergy, the pitch of Said netvvofk being constant thfoI1ghout the length thereof, meanS foT diTecting a beam of eleotrons a1ong a patl1 adiacent Said 11etvvork i1 enefgy interacting Telationship With a backvvard con1ponent of said wave energy, oaid nleans fof difecting including means fof pfodcig n1ntually peI,pendioolaf unidifectional electfio and IIlaglletic fieldS iI1 the TogioI1 of said path and SubStantially nofInal thefeto, an electfode spaced froIn and Snbstantfally coextensivo With said pefiodio nefvofk, and lttaintai1ed at a nogative potentia1 With Tespeot to oaid lletvvofk, iI1pIlf ooupling IneanS positioned adiacent the eIId of Said 11etvvoTk tovvafd vvhich olectfonS aTe difected fof inSerting an inpnt Signal confai11ing at leaSt one diScTeto ffequency con1ponent into Said device, oI1tput neanS discloSed adiacent the end of said notWoTk away ffoIn Which Said electronS are diTected, Said elec tfode being inolined at aI1 angle vith TeSpect to said net Work.

lS. A vvide band traveling vvave eleotfon diSchage devico con1priSing a periodic SlOW vave energy pTopagating netWofk foI tfanSmitting electfomagnetic wve eneT- gy, the pitch of Safd netwofk being constant thronghout 3. Inajor poftion thereof, nleanS for diTecting a bean1 of electfons along a path adiacent said 11etvvork in energy interacting relationShip vvith a. backvvaTd coInponent of Said vvavo energy, Said IneanS f()1 difecting iIlolllding IneanS fof pToducing mutually perpendiculaT unidifectional e1ec tTic d Inagnetic efds in the Tegion of Said path and S11bstantia.11y noTTnal theTeto, an eleotrode S aced ffoln and SubstantiaHy coextonsive With said peTiodio netwoTk, Said s acin bein Snbstan ia11 unifoTn1 fllrou hout the length of Said netWork, and maintained at a negative po tential vVith Tespect to Said 1etvvork, input coupling Ineans poSitioned adjacont the eIld of said netWofk toward vvhich electfonS afo directed for inserting an input signal con taining at leaSt o11e disorete freqUency coInponent into Said device,- and ontput meanS diScloSed adiacent the end of Said netwofk avvay ffoTI1 vvhich said electTons afe direoted, Said electfode being inclined at an angle with fespect to said netWoTk, and said Ineans for pToducing a nlagnetic field including a plUTality of m agnetS of dif ferent neld sfrength poSitioned along said path in he oTdef of their TeSpective field StrengthS.

16, A Wide band tTaveling vvave e1eoron diScharge dovice coInpfiSing a periodic slovv vvave energy pfopa gating netvvork fof tranSn1itting electronlagnetic Wave en ergy, the pitch of Said network being conStant throlgh out a lTlaior poftion thofeof, n1eanS fo1 directing a beaIn of electronS along a path adjacent said netWork in en efgy interacting relationship vvith Said vave enefgy, Said Ineans for directing including meanS for pToducing mU toally perpendicular unidifectional electric and Tnagnetic fieldS i11 the fegion of Said path a11d SubStantiany nornal thereto, an electrode Spaced ffoIn and Substantially co eXtenSive vVith Said pefiodic network, and nlaintained at a negative potentfal vvith Tespect to Said netvvork, input coupling IIleans poSitioned adiacent the end of said flet Work towaTd Which eleofTons aTe diTected fof inseIting an inpnt Signal contaiI1ing at least one discfete frequency conlponent into said device, output IneanS disolosed ad iacent the end of said netwoTk aWay ffom which said electTonS afe difected, Said elecfrode being inclined at an angle vvith Tespect to said I1etvvoTk, and Said nlagnetic field iI1tenSity being SubStantially unifofn] along the length of Said netWork.

17- A Wide band tTaveling vave electfon diScharge de vice CoIflpfiSing a poIiodio slovv Wave enoTgy pTopagating IletvVofk fof tTansIT1itting electfon1agnetic vave enefgy, the 1)itch of Said netvofk being conSta.nt thfoughoIlt a n1aior poftion theTeof, IneanS fof difecting a beann1 of elect1-on along o path adiacent said netvvork in energy interacting felationship vvit1 a baokWoTd conlponent of Said vvave enefgy, Said IIleans fo1 difecting inc111ding Ineans fof pToducing InI1tually perpendiculaf unidifectional electTic and nlagnetic fields in the fegion of Said path and SubSfantially nor1a1 thefeto, an electfode spaced fron1 and subStaJ1tially cooxtenSive vvith Said peTiodic net work, and IIlaiI1tained at a negative potential vvith Tespect to Said netvvoTk, input coUpling n1eanS positioned adjacent the end of Said netWork towaTd Which electTonS aTe difected fof inseTting ra11 inpnt Sigoal contailling at least one diScrete ffequenoy coInponent into said devico, oI1t put means diScloSed adjacent the end of Said network aWay ffon1 vvhic11 Said eleotfonS a1o difeotod, Said elec 11 tfode being inclined at an angle With Tospect to Said not Work, and said magnetio e1d intenSity boing SubStantia1- ly nnifo1II1 along the length of Said netWork.

18. A Wide band fraveling vvave electron diSchaTge de vice coInpriSing a periodio slovv vvave energy pTopagat1g netWork fof tranSInitting electfonlagnefic vave energy, the pitch of said netWoTk being conSfant thToughout the length thereof, means foT diTecti11g a beam of electrons along a path adjacent Said netWork in eneTgy interacting relationShip With sa.id wave energy, said IT1ea11s for diTect ing inclnding meaS for producing Inutually perpendicula1 Unidifectional electfic and Inagnetic fieldS i11 the Tegion of Said path and SIlbStaI1tially norn1al thereto, in )11t co11- li11g nlea.nS )ositioned adjacent the end of Said netWork toWaTd which electrons are diTected for iI1Serting an i11 )I1t signal containing at leaSt one diScfeto ffequency coII1- ponent into said device, ontput nleanS discloSed adiacent the end of Said netWoTk aWay fron1 Which said electrons aTe directed, and means fo1 varying the intenSity of at leaSt one of Said fields a1ong Said path.

19. A Wide band traveli11g Wave electron dischaIge de vice comprising a periodic Slow Wave energy pTopagating netvoTk foT tranSInitti11g electTomagnetic Wave energy, the pitch of Said netWork being constant thonghoUt a major poftion thereof, meanS for diTecting a bean1 of electrons along ath adiacent said netwoTk iI1 energy in teTacting TelationShip With a backWard coInponent of Said wave energy, Said means foT difecting induding meanS fo1 producing mutuany perpendicular unidiTocfiona1 olectric and n1a netic e1dS in the region of Sajd ath and Sub Stantially noTmal thefeto, an electrode Spaced fon1 and SubStantially coextensive with Said pefiodio neWork, and Ina 11tained at a negative potential vvith reS ect to said netvvofk, input coupling n1eanS positioned adiaconf the end of said 11etvork tovard Which electrons aro direcfod for inSeTting an input SigIlal containing at least one dfscrete ffequency conlponent SigT1a1 into said device, out put o1eanS disclosed adjaceI1t the end of said notvvork away fron1 Which Said electfons aIe diected, Said electrode being inclined at an angle With Tespect to said net Work, and Said n1eanS for producig a nlagnetic field including a plufa1ity of n1agnetS of diffefent field strength positioned along Said path in the oTder of their Tespoc tive field StfengthS.

Refeences cifed in the me of this patont UNITED STATES PATENTS Z,70Z,370 Lerbs Feb. 1S, 19

2,730,648 Lerbs Ian. 10, 196

Z,774 913 CharleS Dec. 18 19so Z 807,743 Ciof Sept. Z4, 19S7 FOREIGN PATENTS LO80,027 ETance May Z6, 1954 699,893 GTeat Britain Nov. 18 19S3 

